Embodiments of the present disclosure relate generally to high voltage cable termination, and more particularly to a system and method for underwater termination of high voltage power cables.
Typically, in an oil and gas well, power to electrical components on the sea floor is supplied from sea or land based power sources. In one example, the electrical components may include submerged process control equipment, pumping equipment, compression equipment, motors, and the like. These electrical components may be used to govern the extraction and injection of gas and liquids from the oil and gas well.
In general, high voltage power cables are used to supply power from the sea or land based power sources to these electrical components. Moreover, the high voltage power cables may be electrically connected to the electrical components using sub-sea connectors. Additionally, at large sea depths, multiple high voltage power cables may be required to supply power to these electrical components, thereby necessitating the interconnection of these high voltage power cables via the sub-sea connectors.
Since the sub-sea connectors are used for underwater electrical connections, these connectors may be subjected to harsh environments, such as varying sea water pressure and sea water ingression, which in turn may damage the connectors and/or electrical components. Also, retrieving the connectors for repair entails high expenditure.
In a conventional system, alternate current (AC) power cables and AC connectors are used to supply AC power to the electrical components on the sea floor. However, as oil exploration and drilling activities extend to deeper water depths, power transmission over long distances poses a bigger challenge for AC power cables because of the capacitive load of the cables. Thus, DC power transmission is a highly promising solution for sub-sea electrical components. In addition, the existing AC connectors cannot be used to connect DC power cables for DC power transmission because of special field distribution properties under DC which may lead to failure of the AC connectors.